Soviet
intelligence defector Walter Krivitsky has the first of several
debriefings at the Department of State.

26-June

President Roosevelt secretly
gives the Federal Bureau of Investigation (FBI), the Military
Intelligence Division (MID), and the Office of Naval
Intelligence (ONI) exclusive responsibility for
counterespionage.

23-Aug

Germany and USSR
sign Non-Aggression Pact.

1-Sep

World War II begins as Germany
invades Poland.

1940

21-May

President
Roosevelt authorizes the FBI to conduct warrantless electronic
surveillance of persons suspected of subversion or espionage;
surveillance was to be limited insofar as possible to
aliens.

5-June

FBI-MID-ONI "Delimitation
Agreement" further specifies the division of labor in domestic
intelligence work.

FBI arrests 29 German military
intelligence agents, crippling Germany's clandestine operations
in the United States.

23-July

US Government
allows Ovakimian to leave the country.

25-Sep

London KGB resident Anatoli
Gorski informs Moscow that his agent reports London has decided
to build an atomic bomb.

7-Dec

Japanese
aircraft attack Pearl Harbor; America enters the war.

25-Dec

Senior KGB officer Vassili M.
Zarubin arrives in San Francisco on his way to succeed
Ovakimian as New York resident.

1942

20-Mar

MID's Special
Branch begins producing daily "Magic Summaries" analyzing
foreign diplomatic messages for the White House and senior
military commanders.

13-June

The Office of the Coordinator of
Information becomes the Office of Strategic Services (OSS),
subordinate to the Joint Chiefs of Staff.

30-June

Interagency
agreement divides signals intelligence duties: Navy assigned to
handle naval codebreaking; the US Army's Signals Intelligence
Service to handle diplomatic and military traffic; and the FBI
works clandestine radio communications.

8-July

President Roosevelt bars all
agencies except the FBI and the armed services from
code-breaking activities. The services interpret this directive
as authorization to deny signals intelligence to OSS.

ASA cryptanalyst
Meredith Gardner begins to analytically reconstruct KGB
codebook; decrypts a few messages including one about the
atomic bomb.

20-Dec

M. Gardner decrypts part of a KGB
message containing a list of atomic scientists.

1947

22-Mar

Executive Order
9835 tightens protections against subversive infiltration of
the US Government, defining disloyalty as membership on a list
of subversive organizations maintained by the Attorney
General.

26-July

President Truman signs the
National Security Act of 1947, creating the National Security
Council (NSC) and transforming CIG into the Central
Intelligence Agency (CIA).

NSCID-9 puts
USCIB under the NSC and increases civilian control of signals
intelligence.

20-July

General Secretary Eugene Dennis
and 11 other CPUSA leaders arrested and indicted under the
Smith Act of conspiring to advocate violent overthrow of the US
Government.

31-July

Elizabeth
Bentley testifies before the House Committee on Un-American
Activities (HCUA), publicly accusing Harry Dexter White and
Lauchlin Currie of being Soviet agents.

3-Aug

Whittaker Chambers names Alger
Hiss and Harry Dexter White as Communists in testimony before
the HCUA.

19-Oct

Meredith Gardner
and Robert Lamphere, based at FBI Headquarters, meet at
Arlington Hall and formally inaugurate full-time FBI-ASA
liaison on the Soviet messages. A large number of espionage
cases are opened.

17-Nov

Chambers produces the "Pumpkin
Papers" to substantiate his new charge that Hiss and White
spied for Moscow during the 1930s.

Congress passes
the Internal Security Act (the "McCarran Act"), which it would
soon pass again over President Truman's veto. The Act requires
Communist-linked organizations to register and allows emergency
detention of potentially dangerous persons.

1951

25-May

British Foreign
Office officials Donald MacLean and Guy Burgess flee Great
Britain to defect to the Soviet Union.

July

CPUSA announces that the Party
will operate as a "cadre organization," with many of its
leaders underground.

1952-1953

An earlier KGB
cryptosystem is exploited; GRU messages attacked and broken
down. More espionage agents become identified during the next
two decades.

1952

AFSA detects
duplicate key pages in GRU messages.

4-Nov

Truman creates the National
Security Agency (NSA) to supersede AFSA and further centralize
control of signals intelligence under the Secretary of Defense
and a reconstituted USCIB.

1953

CIA officially
briefed on VENONA and begins to assist in counterintelligence
work.

NSA places the "POBJEDA"
codebook--recovered in Germany in April 1945--against KGB
messages from 1941 through 1943. More than half of the burned
codebook proves useable.

5-Mar

Josef Stalin
dies.

6-Apr

KGB defector Alexander Orlov's
story appears in Life magazine, finally alerting the FBI to his
residence in the United States.

19-June

Julius and Ethel
Rosenberg executed after President Eisenhower again denies
executive clemency.

27-July

Armistice signed in Korea.

6-Nov

Attorney General
Herbert Brownell sparks controversy by claiming in a Chicago
speech that former President Truman had appointed Harry Dexter
White to head the International Monetary Fund despite FBI
warnings that White was a Soviet agent.

1954

20-Dec

CIA's
Directorate of Plans creates the Counterintelligence Staff,
with James J. Angleton as its chief.

1956

8-Mar

NSC approves the
FBI's proposed "COINTELPRO" operation against the CPUSA.

4-June

The Department of State releases
Soviet General Secretary Khrushchev's secret speech to the
Twentieth Party Congress, in which Khrushchev denounced
Stalin's crimes.

October

Soviet troops
suppress a popular uprising in Hungary.

1957

25-Jan

FBI arrests Jack
and Myra Sobel for espionage on the basis of evidence provided
by double agent Boris Morros.

4-May

KGB officer Reino Hayhanen, en
route from the United States, defects at the US Embassy in
Paris.

17-June

Supreme Court in
Yates v. US rules the government had enforced the Smith Act too
broadly by targeting protected speech instead of actual action
to overthrow the political system; this ruling makes the Act
almost useless for prosecuting Communists.

U.K. begins to
exploit Naval GRU messages. From 1960-80, hundreds of
first-time translations of VENONA messages become available;
many earlier translations are reissued.

1980

October 1, the
final work on VENONA comes to a close at Arlington Hall.

July 1995

CIA Director
John Deutsch holds a press conference in Washington, D.C.,
formally announcing the release of the first phase of VENONA
decrypts.

October 1996

The Center for
the Study of Intelligence, the National Security Agency, and
the Center for Democracy co-sponsor ‚€œThe VENONA
Conference‚€, October 3-4, 1996, at the National War
College, Ft. Lesley J. McNair, Washington, DC. The conference
is timed to coincide with the final declassified release of
VENONA message enciphered Soviet telegrams from the 1940s.
After the last release, the total messages number 2,900.